Caltech News tagged with "LIGO"http://www.caltech.edu/news/tag_ids/38/rss.xml
enLIGO Resumes Search for Gravitational Waveshttp://www.caltech.edu/news/ligo-resumes-search-gravitational-waves-53117
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Whitney Clavin</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Ligo-Hanford-NEWS-WEB.jpg?itok=EtcwvgRH" alt="aerial photo of the LIGO facility in Hanford, Washington" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">LIGO Hanford Observatory</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Caltech/MIT/LIGO Lab</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>After a series of upgrades, the twin detectors of LIGO, the Laser Interferometer Gravitational-wave Observatory, have turned back on and resumed their search for ripples in the fabric of space and time known as gravitational waves. LIGO transitioned from engineering test runs to science observations at 8 a.m. Pacific Standard Time on November 30.</p><p>On February 11, 2016, the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration announced that LIGO had made the <a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777">first-ever direct observation of gravitational waves</a>. The waves were generated by a tremendously powerful collision of two black holes 1.3 billion light-years away and were recorded by both of LIGO's detectors—one in Hanford, Washington, and the other in Livingston, Louisiana. <a href="http://www.caltech.edu/news/gravitational-waves-detected-second-pair-colliding-black-holes-51070">A second gravitational-wave detection</a> by LIGO was announced on June 15, 2016, also from merging black holes.</p><p>The initial detections were made during LIGO's first run after undergoing major technical upgrades in a program called Advanced LIGO. That run lasted from September 2015 to January 2016. Since then, engineers and scientists have been evaluating LIGO's performance and making improvements to its lasers, electronics, and optics—resulting in an overall increase in LIGO's sensitivity.</p><p>"For our first run, we made two confirmed detections of black-hole mergers in four months," says Caltech's Dave Reitze, executive director of the LIGO Laboratory, which operates the LIGO observatories. "With our improved sensitivity, and a longer observing period, we will likely observe even more black-hole mergers in the coming run and further enhance our knowledge of black-hole dynamics. We are only just now, thanks to LIGO, learning about how often events like these occur."</p><p>The Livingston detector now has about a 25 percent greater sensitivity—or range for detecting gravitational waves from binary black holes—than during the first observing run. That means it can see black-hole mergers at further distances than before, and therefore should see more mergers than before. The sensitivity for the Hanford detector is similar to that of the first observing run.</p><p>"The Livingston detector has improved sensitivity for lower gravitational-wave frequencies, below about 100 hertz, primarily as the result of reducing the level of scattered light, which can be a pernicious source of noise in the interferometers," says Peter Fritschel, the associate director for LIGO at MIT and LIGO's chief detector scientist. "This is important for detecting massive systems like the merger of two black holes. We are confident that we'll see more black-hole mergers."</p><p>"LIGO Hanford scientists and engineers have successfully increased the power into the interferometer, and improved the stability of the detector," says Caltech's Mike Landry, the head of LIGO Hanford Observatory. "Significant progress has been made for the future utilization of still higher power, which will ultimately lead to improved sensitivity in future runs. Furthermore, with the addition of specialized sensors called balance-beam tilt meters in the corner and end stations, the detector is now more stable against wind and low-frequency seismic motion, thereby increasing the amount of time the detector can be in observing mode."</p><p>The LIGO team will continue to improve the observatories' sensitivities over the coming years, with increases planned for each successive observing run. As more black-hole mergers are detected by LIGO, scientists will start to get their first real understanding of black-hole pairs in the universe—including their population numbers, masses, and spin rates. LIGO may also detect the merger of neutron stars—the dense cores of exploded stars. Knowledge of both black-hole and neutron-star mergers will improve our understanding of stellar evolution and death.</p><p>"LIGO's scientific and operational staff have been working hard for the past year and are enthusiastic to restart round-the-clock observations. We are as curious as the rest of the world about what nature will send our way this year," says LIGO Livingston Observatory head Joe Giaime of Caltech and Louisiana State University.</p><p>Caltech and MIT conceived of, built, and operate the LIGO Observatories, with funding provided by the National Science Foundation (NSF). The Advanced LIGO detector was constructed by Caltech and MIT with funding from NSF and contributions from LSC institutions worldwide, including the Max Planck Society in Germany, the Science and Technology Facilities Council (STFC) in the U.K., and the Australian Research Council, among many others.</p><p>LIGO research is carried out by the international LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the Virgo Collaboration in Europe. </p><p>More information about LIGO and its partners can be found at <a href="http://www.ligo.caltech.edu">www.ligo.caltech.edu</a> and <a href="http://www.ligo.org">www.ligo.org</a>.</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="https://mediaassets.caltech.edu/gwave" class="pr-link">LIGO Visuals</a></div><div class="field-item odd"><a href="https://www.ligo.caltech.edu" class="pr-link">LIGO Laboratory Website</a></div><div class="field-item even"><a href="http://www.ligo.org" class="pr-link">LIGO Scientific Collaboration Website</a></div></div></div>Wed, 30 Nov 2016 00:25:14 +0000wclavin53117 at http://www.caltech.eduGravitational Waves Detected from Second Pair of Colliding Black Holeshttp://www.caltech.edu/news/gravitational-waves-detected-second-pair-colliding-black-holes-51070
<div class="field field-name-field-subtitle field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">The LIGO Scientific Collaboration and the Virgo collaboration identify a second gravitational wave event in the data from Advanced LIGO detectors</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Gravity-Waves-StillImage-NEWS-WEB.jpg?itok=sBaEbAT8" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">This illustration shows the merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. The black holes—which represent those detected by LIGO on Dec. 26, 2015—were 14 and 8 times the mass of the sun, until they merged, forming a single black hole 21 times the mass of the sun. In reality, the area near the black holes would appear highly warped, and the gravitational waves would be difficult to see directly.</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: LIGO/T. Pyle</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>On December 26, 2015 at 03:38:53 UTC, scientists observed gravitational waves—ripples in the fabric of spacetime—for the second time.</p><p>The gravitational waves were detected by both of the twin Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA.</p><p>The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. <a href="http://resolver.caltech.edu/CaltechAUTHORS:20160615-122950563">The discovery</a>, accepted for publication in the journal <em>Physical Review Letters</em>, was made by the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the Virgo Collaboration using data from the two LIGO detectors.</p><p>Gravitational waves carry information about their origins and about the nature of gravity that cannot otherwise be obtained, and physicists have concluded that these gravitational waves were produced during the final moments of the merger of two black holes—14 and 8 times the mass of the sun—to produce a single, more massive spinning black hole that is 21 times the mass of the sun.</p><p>"It is very significant that these black holes were much less massive than those observed in the first detection," says Gabriela Gonzalez, LIGO Scientific Collaboration (LSC) spokesperson and professor of physics and astronomy at Louisiana State University. "Because of their lighter masses compared to the first detection, they spent more time—about one second—in the sensitive band of the detectors. It is a promising start to mapping the populations of black holes in our universe."</p><p>During the merger, which occurred approximately 1.4 billion years ago, a quantity of energy roughly equivalent to the mass of the sun was converted into gravitational waves. The detected signal comes from the last 27 orbits of the black holes before their merger. Based on the arrival time of the signals—with the Livingston detector measuring the waves 1.1 milliseconds before the Hanford detector—the position of the source in the sky can be roughly determined.</p><p>"In the near future, Virgo, the European interferometer, will join a growing network of gravitational wave detectors, which work together with ground-based telescopes that follow-up on the signals," notes Fulvio Ricci, the Virgo Collaboration spokesperson, a physicist at Istituto Nazionale di Fisica Nucleare (INFN) and professor at Sapienza University of Rome. "The three interferometers together will permit a far better localization in the sky of the signals."</p><p><a href="/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777">The first detection of gravitational waves</a>, announced on February 11, 2016, confirmed a major prediction of Albert Einstein's 1915 general theory of relativity, and marked the beginning of the new field of gravitational-wave astronomy.</p><p>The second discovery "has truly put the 'O' for Observatory in LIGO," says Caltech's Albert Lazzarini, deputy director of the LIGO Laboratory. "With detections of two strong events in the four months of our first observing run, we can begin to make predictions about how often we might be hearing gravitational waves in the future. LIGO is bringing us a new way to observe some of the darkest yet most energetic events in our universe."</p><p>"We are starting to get a glimpse of the kind of new astrophysical information that can only come from gravitational wave detectors," says MIT's David Shoemaker, who led the Advanced LIGO detector construction program.</p><p>Both discoveries were made possible by the enhanced capabilities of Advanced LIGO, a major upgrade that increases the sensitivity of the instruments compared to the first generation LIGO detectors, enabling a large increase in the volume of the universe probed.</p><p>"With the advent of Advanced LIGO, we anticipated researchers would eventually succeed at detecting unexpected phenomena, but these two detections thus far have surpassed our expectations," says NSF Director France A. Córdova. "NSF's 40-year investment in this foundational research is already yielding new information about the nature of the dark universe."</p><p>Advanced LIGO's next data-taking run will begin this fall. By then, further improvements in detector sensitivity are expected to allow LIGO to reach as much as 1.5 to 2 times more of the volume of the universe. The Virgo detector is expected to join in the latter half of the upcoming observing run.</p><p>LIGO research is carried out by the LIGO Scientific Collaboration (LSC), a group of more than 1,000 scientists from universities around the United States and in 14 other countries. More than 90 universities and research institutes in the LSC develop detector technology and analyze data; approximately 250 students are strong contributing members of the collaboration. The LSC detector network includes the LIGO interferometers and the GEO600 detector.</p><p>Virgo research is carried out by the Virgo Collaboration, consisting of more than 250 physicists and engineers belonging to 19 different European research groups: 6 from Centre National de la Recherche Scientifique (CNRS) in France; 8 from the Istituto Nazionale di Fisica Nucleare (INFN) in Italy; 2 in The Netherlands with Nikhef; the MTA Wigner RCP in Hungary; the POLGRAW group in Poland and the European Gravitational Observatory (EGO), the laboratory hosting the Virgo detector near Pisa in Italy.</p><p>The NSF provides most of the financial support for Advanced LIGO. Funding organizations in Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council, STFC) and Australia (Australian Research Council) also have made significant commitments to the project.</p><p>Several of the key technologies that made Advanced LIGO so much more sensitive have been developed and tested by the German UK GEO collaboration. Significant computer resources have been contributed by the AEI Hannover Atlas Cluster, the LIGO Laboratory, Syracuse University, the ARCCA cluster at Cardiff University, the University of Wisconsin-Milwaukee, and the Open Science Grid. Several universities designed, built, and tested key components and techniques for Advanced LIGO: The Australian National University, the University of Adelaide, the University of Western Australia, the University of Florida, Stanford University, Columbia University in the City of New York, and Louisiana State University. The GEO team includes scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI), Leibniz Universität Hannover, along with partners at the University of Glasgow, Cardiff University, the University of Birmingham, other universities in the United Kingdom and Germany, and the University of the Balearic Islands in Spain.</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://mediaassets.caltech.edu/gwave2" class="pr-link">Related videos, images, and audio</a></div><div class="field-item odd"><a href="http://bit.ly/ligochirptones" class="pr-link">Download gravitational wave "chirp" ringtones</a></div></div></div>Tue, 14 Jun 2016 22:29:01 +0000wclavin51070 at http://www.caltech.eduLive Webcast: LIGO, Virgo Scientists to Discuss Continued Search for Gravitational Waveshttp://www.caltech.edu/news/live-webcast-ligo-virgo-scientists-discuss-continued-search-gravitational-waves-51069
<div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/LIGO_logo-high_res.jpg?itok=h630Hd9D" alt="" /></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>The latest research in the effort to detect gravitational waves will be discussed in a press briefing at the 228th meeting of the American Astronomical Society in San Diego, California. The public can view the briefing during the <a href="https://aas.org/aas-briefing-webcast">live webcast</a>, scheduled to begin at 10:15 am Pacific Daylight Time on Wednesday, June 15, 2016. The panelists for the briefing are Caltech's David Reitze, executive director of LIGO; Gabriela González, LIGO Scientific Collaboration spokesperson, from Louisiana State University; and Fulvio Ricci, Virgo spokesperson, from the University of Rome Sapienza and the Istituto Nazionale di Fisica Nucleare in Rome.</p><p><a href="http://aas.org/aas-briefing-webcast" target="_blank"><img src="http://dabuttonfactory.com/button.png?t=VIEW+THE+LIVE+PRESS+CONFERENCE&amp;f=Calibri-Bold&amp;ts=18&amp;tc=fff&amp;tshs=1&amp;tshc=000&amp;hp=20&amp;vp=8&amp;c=5&amp;bgt=gradient&amp;bgc=3d85c6&amp;ebgc=073763" /></a></p><p><a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777">The first detection of gravitational waves</a>, announced on February 11, 2016, confirmed a major prediction of Albert Einstein's 1915 general theory of relativity, and marked the beginning of the new field of gravitational-wave astronomy.</p><p>LIGO, a system of two identical detectors located in Livingston, Louisiana, and Hanford, Washington, was constructed to detect the tiny vibrations from passing gravitational waves, was conceived and built by Caltech and MIT with funding from the National Science Foundation and contributions from other U.S. and international partners.</p></div></div></div>Tue, 14 Jun 2016 22:13:20 +0000rbasu51069 at http://www.caltech.eduLIGO Founders Receive Prestigious Kavli Prize in Astrophysicshttp://www.caltech.edu/news/ligo-founders-receive-prestigious-kavli-prize-astrophysics-50878
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Whitney Clavin</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Thorne-NEWS-WEB.jpg?itok=oGYlWuCd" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Kip Thorne, the Richard P. Feynman Professor of Theoretical Physics, Emeritus, Caltech</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Caltech Alumni Association</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>The 2016 <a href="http://www.kavliprize.org/">Kavli Prize</a> in Astrophysics has been awarded to the three founders of the Laser Interferometer Gravitational-Wave Observatory (LIGO): Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne (BS '62), the Richard P. Feynman Professor of Theoretical Physics, Emeritus; and MIT's Rainer Weiss, professor of physics, emeritus.</p><p>The $1 million prize, presented once every two years, honors the three for their instrumental role in establishing LIGO, an effort that led to the direct detection of gravitational waves—ripples in the fabric of space and time predicted a century earlier by Albert Einstein's general theory of relativity. On February 11, 2016, the <a href="/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777">international LIGO team announced</a> the first observation of gravitational waves arriving at Earth.</p><p>The waves were generated 1.3 billion years ago when two black holes spiraled around each other and ultimately merged to form a single, more massive black hole. The twin LIGO instruments—one in Hanford, Washington, and the other in Livingston, Louisiana—detected the waves by measuring changes to the lengths of their 4-kilometer-long arms as small as one one-thousandth the width of a proton.</p><p>"The detection of tiny ripples in space and time, set up when two black holes merged more than a billion years ago, is one of the most amazing feats of the century," says Fiona Harrison, the Benjamin M. Rosen Professor of Physics and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy. "The LIGO project is a marvel of precision measurement, engineering, and technical ingenuity. Its founders, Kip, Rai, and Ron, and the entire LIGO team, deserve credit for this amazing discovery."</p><p>The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO.</p><p>On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves.</p><p>"The lion's share of the credit for LIGO's gravitational wave discovery belongs to the superb 1000-member LIGO team, who pulled it off," said Thorne. "They have made Weiss, Drever and me look good. And my deep thanks go out, also, to the succession of outstanding LIGO directors who provided the leadership required for success—Robbie Vogt, Stan Whitcomb, Jay Marx, David Reitze, and especially Barry Barish. Barry designed and led the transformation of LIGO from the small R&amp;D project that Weiss, Drever and I created into the wonderfully successful big-science project that it is today."</p><p>According to <a href="http://www.kavliprize.org/prizes-and-laureates/prizes/2016-kavli-prize-astrophysics">the Kavli award citation</a>, "the direct measurement of the tiny space-time ripples required the sustained vision and experimental ingenuity of Drever, Thorne and Weiss, spanning most of the last 50 years, as individual scientists and later as intellectual leaders of a team of hundreds of scientists and engineers."</p><p>The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The LIGO discovery team consists of the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the European Virgo Collaboration. The NSF leads in financial support for Advanced LIGO. Funding organizations in Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council, STFC) and Australia (Australian Research Council) also have made significant commitments to the project.</p><p>The Kavli Prizes, established in 2008 and awarded every two years, recognize scientists for their seminal advances in three research areas: astrophysics, nanoscience, and neuroscience. Each prize consists of a scroll, a medal, and a cash award. The Kavli Prizes are presented in cooperation and partnership with the Norwegian Academy of Science and Letters and the Norwegian Ministry of Education and Research.</p><p>Past Caltech winners of the Kavli Prize in Astrophysics include Mike Brown, the Richard and Barbara Rosenberg Professor and Professor of Planetary Astronomy, who <a href="/news/caltech-astronomer-mike-brown-awarded-kavli-prize-astrophysics-4202">received the Kavli Prize in 2012</a> for <span style="color: rgb(34, 34, 34); font-family: Vaud, sans-serif; font-size: 14px;">work that led to a major advance in the understanding of the history of our planetary system</span>, and Maarten Schmidt, the Frances L. Moseley Professor of Astronomy, Emeritus, who was <a href="/news/astrophysicist-wins-one-first-kavli-prizes-1437">awarded the prize in 2008</a> for his seminal contributions to our understanding of the nature of quasars. Other Kavli Prize recipients include alumni David C. Jewitt (MS '80, PhD '83), cowinner of the 2012 Kavli Prize for Astrophysics; James Roger Angel (MS '66), cowinner of the 2010 Kavli Prize in Astrophysics; and Caltech trustee Richard H. Scheller (PhD '80), cowinner of the 2010 Kavli Prize in Neuroscience. </p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777" class="pr-link">Gravitational Waves Detected 100 Years After Einstein’s Prediction</a></div></div></div>Wed, 01 Jun 2016 22:51:03 +0000wclavin50878 at http://www.caltech.edu2016 Shaw Prize Awarded to LIGO Foundershttp://www.caltech.edu/news/2016-shaw-prize-awarded-ligo-founders-50845
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Whitney Clavin</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/LIGO_Livingston-NEWS-WEB.jpg?itok=fHeZsO-C" alt="Aerial photograph of LIGO Livingston facility" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">LIGO Livingston, one of two LIGO detectors, is located in Livingston, Louisiana. The other facility, not pictured, is in Hanford, Washington. </div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Caltech/MIT/LIGO Lab</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>This year's Shaw Prize in Astronomy, worth $1.2 million, has been awarded to the trio of researchers who founded LIGO: Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne (BS '62), the Richard P. Feynman Professor of Theoretical Physics, Emeritus; and MIT's Rainer Weiss, professor of physics, emeritus.</p><p>According to the prize announcement, the LIGO founders are being honored "for conceiving and designing the Laser Interferometer Gravitational-Wave Observatory (LIGO), whose recent direct detection of gravitational waves opens a new window in astronomy, with the first remarkable discovery being the merger of a pair of stellar mass black holes."</p><p>The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO. On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves—the result of the collision of two black holes to form a single, more massive black hole. The detection was announced on February 11, 2016.</p><p>Drever, Thorne and Weiss have also jointly received the <a href="/news/ligo-founders-and-team-receive-cosmology-prize-50727">2016 Gruber Foundation Cosmology Prize</a> and the <a href="/news/ligo-team-awarded-special-breakthrough-prize-fundamental-physics-50657">2016 Breakthrough Prize in Fundamental Physics</a> for their contributions to LIGO.</p><p>The Shaw Prize, established in 2004, is awarded annually in three categories: Astronomy, Life Science and Medicine, and Mathematical Sciences. It "honors individuals, regardless of race, nationality, gender and religious belief, who have achieved significant breakthroughs in academic and scientific research or applications and whose work has resulted in a positive and profound impact on mankind," according to the Prize website.</p><p><a href="http://www.shawprize.org/">The Shaw Prize</a> is an international award managed and administered by The Shaw Prize Foundation based in Hong Kong. Mr. Shaw has also founded The Sir Run Run Shaw Charitable Trust and The Shaw Foundation Hong Kong, both dedicated to the promotion of education, scientific and technological research, medical and welfare services, and culture and the arts.</p></div></div></div>Wed, 01 Jun 2016 17:20:11 +0000wclavin50845 at http://www.caltech.eduLIGO Founders and Team Receive Cosmology Prizehttp://www.caltech.edu/news/ligo-founders-and-team-receive-cosmology-prize-50727
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Lori Dajose</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Drever_Orig.jpg?itok=FndyU6gt" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Ronald Drever</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Photo courtesy of the Gruber Foundation</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://pma.caltech.edu/content/ronald-w-drever">Ronald Drever</a>, professor of physics, emeritus; <a href="https://pma.caltech.edu/content/kip-s-thorne">Kip Thorne</a>, Richard P. Feynman Professor of Theoretical Physics, Emeritus; Rai Weiss, MIT professor of physics, emeritus; and the Laser Interferometer Gravitational-Wave Observatory (LIGO) discovery team have been selected to receive the 2016 Gruber Foundation Cosmology Prize for their observation of gravitational waves, distortions in the fabric of spacetime. The Cosmology Prize honors a leading cosmologist, astronomer, astrophysicist, or scientific philosopher for theoretical, analytical, conceptual, or observational discoveries leading to fundamental advances in our understanding of the universe.</p><p>In a press release, the Gruber Foundation called the detection of gravitational waves a "technologically herculean and scientifically transcendent achievement."</p><p>The existence of gravitational waves was predicted by Albert Einstein's 1915 general theory of relativity, but it was not until the 1960s that technological and theoretical advances made detection even possible to consider. In the 1970s, Thorne founded a research group at Caltech to study the theory of gravitational waves. Weiss had developed a design for a gravitational wave detector; he and Thorne recruited Drever, one of the leading creators of gravitational-wave interferometer prototypes, to lead what would become LIGO. On September 14, 2015, during the first observations with the newly upgraded Advanced LIGO interferometers, LIGO detected the first signal of gravitational waves—the result of the collision of two black holes to produce a single, more massive black hole. The detection was announced on February 11, 2016.</p><p>The Gruber Foundation Cosmology Prize includes a $500,000 award, to be divided equally among Drever, Thorne, and Weiss. Each will also receive a gold medal.</p><p>Past recipients of the prize include Caltech's <a href="https://pma.caltech.edu/content/charles-chuck-steidel">Charles Steidel</a>, the Lee A. DuBridge Professor of Astronomy, who received the Gruber Prize in 2010 for his studies of the distant universe.</p><p>The award ceremony will take place on July 12 at the 21st International Conference on General Relativity and Gravitation, held at Columbia University in the City of New York.</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://www.caltech.edu/news/ligo-team-awarded-special-breakthrough-prize-fundamental-physics-50657" class="pr-link">LIGO Team Awarded Special Breakthrough Prize in Fundamental Physics</a></div><div class="field-item odd"><a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777" class="pr-link">Gravitational Waves Detected 100 Years After Einstein’s Prediction</a></div></div></div>Thu, 12 May 2016 20:40:10 +0000ldajose50727 at http://www.caltech.eduLIGO Team Awarded Special Breakthrough Prize in Fundamental Physicshttp://www.caltech.edu/news/ligo-team-awarded-special-breakthrough-prize-fundamental-physics-50657
<div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Breakthrough-Prize-Trophy-RV-NEWS-WEB.jpg?itok=O952xXqL" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">The Breakthrough Prize trophy was created by Olafur Eliasson. “The whole idea for me started out with, ‘Where do these great ideas come from? What type of intuition started the trajectory that eventually becomes what we celebrate today?’” Like much of Eliasson&#039;s work, the sculpture explores the common ground between art and science. It is molded into the shape of a toroid, recalling natural forms found from black holes and galaxies to seashells and coils of DNA.</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Courtesy of the Breakthrough Prize</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>The Selection Committee of the Breakthrough Prize in Fundamental Physics <a href="https://breakthroughprize.org/News/32">has announced</a> a Special Breakthrough Prize in Fundamental Physics recognizing the scientists and engineers who contributed to the detection of gravitational waves by the Laser Interferometer Gravitational-wave Observatory (LIGO).</p><p>The $3 million award is being shared between two groups of laureates. The three founders of LIGO—Caltech's Ronald W. P. Drever, professor of physics, emeritus, and Kip S. Thorne, the Feynman Professor of Theoretical Physics, emeritus; and MIT's Rainer Weiss, professor of physics, emeritus—will share $1 million equally. In addition, 1,012 contributors will equally share $2 million; of these, 1,005 are the authors of the paper from the LIGO and Virgo collaborations, while the remaining seven are scientists who "made important contributions to the success of LIGO." This group of seven includes Caltech's Mark Scheel, senior research associate in physics, and Rochus E. Vogt, the R. Stanton Avery Distinguished Service Professor and Professor of Physics, Emeritus.</p><p>In announcing the special prize, Yuri Milner, one of the founders of the Breakthrough Prizes, said, "The creative powers of a unique genius, many great scientists, and the universe itself, have come together to make a perfect science story."</p><p>For more about Caltech's Breakthrough Prize in Fundamental Physics laureates, read <a href="https://eands.caltech.edu/glitz-qubits/">Glitz and Qubits</a> in the current issue of Caltech's <a href="https://eands.caltech.edu/"><em>E&amp;S</em></a> magazine.</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://www.caltech.edu/news/two-caltech-alumni-receive-breakthrough-prize-48730" class="pr-link">Two Caltech Alumni Receive Breakthrough Prize</a></div><div class="field-item odd"><a href="http://www.caltech.edu/news/john-h-schwarz-wins-fundamental-physics-prize-41536" class="pr-link">John H. Schwarz Wins the Fundamental Physics Prize</a></div><div class="field-item even"><a href="http://www.caltech.edu/news/caltech-cell-biologist-wins-3-million-breakthrough-prize-life-sciences-41525" class="pr-link">Caltech Cell Biologist Wins $3 Million Breakthrough Prize in Life Sciences</a></div></div></div>Tue, 03 May 2016 20:41:05 +0000abenter50657 at http://www.caltech.eduStudents and Postdocs Helped Make Sure LIGO Was Listening http://www.caltech.edu/news/students-and-postdocs-helped-make-sure-ligo-was-listening-50129
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Kimm Fesenmaier</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/LIGO-CIT-Students_0156-NEWS-WEB.jpg?itok=jNEvLJ7C" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Evan Hall (seated) a Caltech Graduate Student and Kiwamu Izumi (standing) a Caltech Postdoctoral Scholar at work in the control room at the LIGO, Hanford facility.</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Rana Adhikari/Caltech</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>In the months leading up to the first detection of gravitational waves by LIGO (the Laser Interferometer Gravitational-wave Observatory), announced on February 11, Caltech postdoctoral scholar Sheila Dwyer and graduate student Evan Hall spent most of their waking hours in the control room at the LIGO Hanford Observatory in the remote plains of southern Washington. The observatory is one in a pair of giant interferometers built and operated by the LIGO Scientific Collaboration with funding from the National Science Foundation to search for the waves—ripples in the fabric of space-time.</p><p>Looking something like NASA's mission control rooms, where space missions are monitored, the LIGO control room has no windows. Instead, there are many monitors displaying camera feeds and plots that provide information about how the interferometer is working. To the uninitiated, the data feeds might be unintelligible. But, Dwyer says, "If you are used to spending time in the control room, you can instantly get an idea of how the interferometer is doing the moment you step into the room."</p><p>"Hours and hours go by where they're sitting at their computer consoles, not saying a word," says Rana Adhikari, Caltech professor of physics and Dwyer and Hall's advisor. " If you don't know what's going on, you might think that nothing is happening. But what they're doing is adjusting slightly the control algorithms which make the whole thing run. "</p><p>Indeed, Dwyer and Hall are part of a relatively small team whose job it is to make sure that the interferometer in Hanford is up and running at its best. There is a similar team in place at the second LIGO observatory in Livingston, Louisiana. A number of Caltech graduate students and postdocs have played pivotal roles in getting the two interferometers operating with enough sensitivity to detect the tiny signal of gravitational waves that came through at 5:51 a.m. EDT on Monday, September 14, 2015.</p><p>"It might be hard for people to understand because LIGO is such a big project, but everything actually depends on the grad students and postdocs, their attitudes, and what's going on with them," says Adhikari. "If they're really excited and interested, and they're really good, it's surprising how quickly the whole project moves."</p><p>Why? Because the students live and breathe the project, and they become experts on the instrument. "They are there day and night, during the week and on weekends," says Adhikari. "After several months of living like that, they get to a level of expertise that can't be matched." (He should know. He himself was once a graduate student working on LIGO.)</p><p>And the project requires that degree of dedication and expertise. Consider what LIGO does: It tries to detect the tiny effect that gravitational waves, often produced trillions upon trillions of miles away, have on the earth as they race by at the speed of light. In the case of LIGO's first detection, the ripples were produced 1.3 billion years ago by a type of event that is among the universe's most energetic—the merger of two black holes. Still, those waves squeezed and stretched space and time only ever so slightly as they passed through the earth. In fact, in order to detect the gravitational waves, LIGO had to be able to detect a change in distance of about one-thousandth the diameter of a proton (10<sup>-18 </sup>meter). </p><p>The twin LIGO interferometers are based on a fairly simple concept: laser light fired down two identical 4-kilometer lengths (situated in an "L" shape) toward identical mirrors should bounce back to their point of origin at the same time; a difference in the two arrival times could be caused by gravitational waves compressing space-time a tiny bit along one length while stretching it a similar amount along the other.</p><p>Those mirrors, and the entire apparatus within which they are contained, sit on the ever-moving earth. For the LIGO detectors to be able to pick out the motion associated with incoming gravitational waves, the interferometer must first be isolated from all other possible sources of movement—noise which could otherwise overwhelm the signal. Everything from seismic activity and wind, to trucks on the road and the hum of lights, to the minuscule quantum vibrations present in all objects can potentially jiggle the mirrors.</p><p>The current generation of LIGO detectors, installed in what is known as Advanced LIGO, marks a technical upgrade to Initial LIGO, which completed its observations in 2007, and a modified intermediate called Enhanced LIGO, which ran until 2010. Advanced LIGO is about four times more sensitive to gravitational waves signals than Enhanced LIGO and has a sophisticated system in place to silence extraneous noise. In addition to operating in an elaborate vacuum (as LIGO always has) the system incorporates layer upon layer of noise-canceling technology based on the same underlying concept behind noise-canceling headphones. Measurements from vibration sensors on a hanging platform are fed to a computer that then tells an actuator how much to compensate, or push, in order to cancel out the noise. Another platform with slightly better sensors is suspended from the first and performs essentially the same trick. This is repeated three times, with each platform removing from 90 to 99 percent of the remaining noise so that in the end, the system currently removes all but 0.1 percent. In addition, the mirrors are held steady by a multiple pendulum system that also helps reflect movement.</p><p>"It's a huge, huge engineering effort to make that work," says Adhikari. "Each component is a crazy system of wires and cables, and each platform has to be isolated from as much movement as possible. You need multiple, multiple sensors on each one doing feedback."</p><p>At the Livingston observatory, Denis Martynov (PhD '15), a former graduate student from Adhikari's group, spent two years tweaking the system—stabilizing the laser, aligning the mirrors precisely relative to each other, and helping to identify and then eliminate different types of noise in the instrument (something he calls "noise hunting"). For example, he and his colleagues discovered that electrostatic charge builds up on the surfaces of the interferometer's mirrors, allowing the electric field present in the instrument to push the mirrors slightly. He also worked on many of the noise-canceling techniques to improve the instrument's sensitivity.</p><p>Hall transferred many of those techniques to the Hanford facility. Although everything about the two interferometers—from their mirrors, to their suspensions, to their placement within the vacuum system—was designed to be identical, there were minor differences between the two instruments. "In some cases, the mirror position might differ by a few millimeters, or the curvature of a mirror may be slightly different," explains Hall. "Little things like that are enough to make the two detectors behave very differently." Hall and his colleagues had to figure out clever engineering tricks to make the two instruments behave like true twins.</p><p>Thanks to efforts like these, Advanced LIGO is a trillion times quieter than the motion of the earth. But its complexity also means that there are more things that can break, get out of alignment, or not work together properly.</p><p>"There are a lot of tweaks and tune-ups that have to be carried out in order to achieve good noise performance," says Hall. "However, it's not always obvious what these tweaks are. Often they can be things like a faulty piece of electronics, or a mirror that's not properly secured to an optical table. Those sorts of things take a lot of time to find, even if the fix is simple."</p><p>At 1:18 a.m. on Sunday, September 14—just a day before both LIGO facilities made their first detection—seismic waves from a series of earthquakes in Mexico affected the Hanford site. Though well over 1,000 miles away, the quakes left Dwyer and her colleagues with quite a bit of work to do. To protect the equipment, the isolation systems turn off during large seismic events, but the delicate instruments can still be disturbed. After the ground motion settled, the team began isolating all the seismic isolation platforms again, but had difficulty with one platform. While trying to recover from the earthquake and realign the optics, Dwyer and the team also found a glitch in the software that runs the system; it had been causing one of the optics to move when it was not supposed to. In all, it took the team in Hanford about 18 hours to get the instrument back up and running.</p><p>Dwyer came in that Sunday hoping to work on a pet project she hoped to finish before the start of the official observing run. "But because of the earthquake, we spent the day fixing more mundane problems, just trying to get the interferometer functional," she says.</p><p> It is a good thing they did because the following night, both LIGO facilities were ready to hear their first gravitational waves.</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://www.caltech.edu/news/ligo-panel-peers-new-window-universe-50012" class="pr-link">LIGO Panel Peers into New Window on the Universe</a></div><div class="field-item odd"><a href="http://www.caltech.edu/news/building-worlds-most-sensitive-detectors-conversation-rana-adhikari-40836" class="pr-link">Building the World's Most Sensitive Detectors: A Conversation with Rana Adhikari</a></div><div class="field-item even"><a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777" class="pr-link">Gravitational Waves Detected 100 Years After Einstein's Prediction </a></div><div class="field-item odd"><a href="http://www.caltech.edu/content/brief-history-ligo" class="pr-link">A Brief History of LIGO</a></div><div class="field-item even"><a href="https://www.youtube.com/watch?v=HOeGVrm8ZFE" class="pr-link">Video: Two Black Holes Merge Into One </a></div><div class="field-item odd"><a href="https://www.youtube.com/watch?v=wrqbfT8qcBc" class="pr-link">Video: LIGO: The First Observation of Gravitational Waves</a></div></div></div>Thu, 10 Mar 2016 20:06:00 +0000kfesenma50129 at http://www.caltech.eduThe Thunder of Gravity in the Cosmoshttp://www.caltech.edu/news/thunder-gravity-cosmos-50029
<div class="field field-name-field-subtitle field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Watson Lecture Preview</div></div></div><div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Lori Dajose</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Adhikara-Rana_7543-NEWS-WEB_1.jpg?itok=c3mje77N" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Rana Adhikari</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Lance Hayashida</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>In 1916, Albert Einstein predicted the existence of gravitational waves—vibrations in spacetime that travel at the speed of light and are produced by the most cataclysmic events in the universe, such as the collision of black holes. Over the past 45 years, scientists have been developing ever-more-sensitive detectors, which are now capable of measuring these distortions from hundreds of millions of light years away. On September 14th, two of those detectors—as part of the Laser Interferometer Gravitational-wave Observatory, or LIGO—picked up <a href="http://www.caltech.edu/gwave">the gravitational vibrations of a pair of massive black holes from a billion years ago</a>.</p><p>On <a href="http://www.caltech.edu/content/rana-adhikari-listening-thunder-gravity-cosmos">Wednesday, March 9, at 8 p.m.</a> in Beckman Auditorium, Caltech professor of physics Rana Adhikari will describe how our understanding of the quantum physics of the very, very small has allowed us to explore the gravitational physics of the very, very large. Admission is free.</p><h3>What do you do?</h3><p>I am an experimental physicist. My overarching obsession is to use experiments to reveal the true nature of the universe.</p><p>We have been learning about the universe through precision experiments in the laboratory and by pushing the limits of astronomical instruments for many years. The recent discovery of gravitational waves from a binary black hole merger allows us to observe the warping of spacetime. This is a chance for us to use quantum physics to extend our knowledge of Einsteinian gravity.</p><h3>Why is this important?</h3><p>Our knowledge of how the universe really works comes to us when we as a people make a bold step by measuring something about nature much better than ever before. The upgraded LIGO detectors have radically expanded our view of the universe. For the first time, humanity is able to receive signals from across the universe made entirely by gravity. The dark side of the universe is being revealed for the first time.</p><h3>How did you get into this line of work?</h3><p>I've had great teachers and mentors! Doing laboratory work in physics and chemistry has always been the most fun thing to do and I was amazed that it is possible to do that for a living. Where else is 'unlocking the secrets of the universe' part of the job description?</p></div></div></div><div class="field field-name-field-pr-links field-type-link-field field-label-above"><div class="field-label">Related Links:&nbsp;</div><div class="field-items"><div class="field-item even"><a href="http://www.caltech.edu/master-calendar/public-events-series/9281/2015-2016" class="pr-link">2015-2016 Earnest C. Watson Lecture Series</a></div></div></div>Fri, 04 Mar 2016 05:19:08 +0000schabner50029 at http://www.caltech.eduLIGO Panel Peers into New Window on the Universehttp://www.caltech.edu/news/ligo-panel-peers-new-window-universe-50012
<div class="field field-name-news-writer field-type-ds field-label-inline clearfix"><div class="field-label">News Writer:&nbsp;</div><div class="field-items"><div class="field-item even">Lori Dajose</div></div></div><div class="field field-name-field-images field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div class="ds-1col file file-image file-image-jpeg view-mode-full_grid_9 clearfix ">
<img src="http://s3-us-west-1.amazonaws.com/www-prod-storage.cloud.caltech.edu/styles/article_photo/s3/Ripples_in_Spacetime-REHEARSAL-3319-NEWS-WEB.jpg?itok=kgbxKYwz" alt="" /><div class="field field-name-field-caption field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">From left to right: Fiona Harrison, the Benjamin M. Rosen Professor of Physics and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy; Kip Thorne, the Richard P. Feynman Professor of Theoretical Physics, Emeritus; and Barry Barish, the Ronald and Maxine Linde Professor of Physics, Emeritus</div></div></div><div class="field field-name-credit-sane-label field-type-ds field-label-hidden"><div class="field-items"><div class="field-item even">Credit: Lance Hayashida/Caltech</div></div></div></div></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>On September 14, 2015, the twin Laser Interferometry Gravitational-wave Observatory (LIGO) detectors sensed the infinitesimal vibrations of a black hole merger that took place over one billion years ago. This discovery, <a href="http://www.caltech.edu/news/gravitational-waves-detected-100-years-after-einstein-s-prediction-49777">announced worldwide on February 11, 2016</a>, has opened a new window on the universe. On February 23, Caltech held a public event to discuss the discovery of gravitational waves and what it will mean for our ongoing exploration and understanding of the universe.</p><p>A panel of scientists from Caltech and LIGO—moderated by Fiona Harrison, the Benjamin M. Rosen Professor of Physics and the Kent and Joyce Kresa Leadership Chair of the Division of Physics, Mathematics and Astronomy—gave a series of short talks describing their experiences with the project.</p><p>Opening remarks were delivered by President Thomas Rosenbaum, who described the discovery of gravitational waves as a "connecting of heaven and earth," likening it to the 18th-century image of lightning striking a key on a kite string. He commended the extraordinary four-decade-long vision of the project and said that it demonstrated how the combination of people and technology could change the world.</p><p>According to panelist Kip Thorne, the Richard P. Feynman Professor of Theoretical Physics, Emeritus, who has been working on the search for gravitational waves since the 1960s, and who detailed for the audience the setup of the identical detectors (located in Hanford, Washington, and Livingston, Louisiana), "Caltech's support for this project has never faltered since the beginning," he said. "It's very impressive."</p><p>"This is the biggest project the National Science Foundation has ever taken on," noted Barry Barish, the Ronald and Maxine Linde Professor of Physics, Emeritus, who described the history of building the detectors and the plans to improve their sensitivities. The NSF, he said, "never wavered, even in this high-risk endeavor. What we have just done in detecting gravitational waves is not the end of the story."</p><p>In their talks, Professor of Physics Rana Adhikari, and Anamaria Effler (BS '06), a postdoctoral scholar at the LIGO Livingston Observatory, described the painstaking effort needed to achieve and maintain the sensitivities of the LIGO detectors—which, after the Advanced LIGO technical upgrade, became the most precise measuring instrument ever constructed. Adhikari discussed the steps to limit Earth's own gravitational noise, the material science behind the superreflective mirrors used in the detectors, and the "squeezed-light system" used to minimize quantum-mechanical noise. Effler talked about the challenge of reducing environmental noise—from earthquakes, oceanic storms, planes, lightning storms, and even air-conditioning units. "Detecting a gravitational wave is like trying to hear someone at the back of a room scratch their nose, while everyone else in the room is screaming," she said.</p><p>Stan Whitcomb, LIGO chief scientist, described plans to add more detectors around the globe—<a href="http://www.caltech.edu/news/ligo-india-gets-green-light-49859">including a LIGO detector in India</a>—enabling scientists to more accurately locate the sources of gravitational waves. Whitcomb also expressed the need for accurate predictions of the gravitational-wave signals that would be produced by other cosmic phenomena—such as the mergers of neutron stars, which are extremely dense stars—in order to recognize them when they happen.</p><p>Mansi Kasliwal, an assistant professor of astronomy, described future efforts to characterize such events that produce gravitational waves. "There should be an immense flash of light, when these events occur. We use telescopes around the world to look at the sky for these flashes, and narrow down which one could have produced the gravitational waves," said Kasliwal, whose group has already successfully identified sources of gamma-ray bursts with this method.</p><p>Several of the panelists described their reactions shortly after the September 14 detection.</p><p>Mike Landry, the lead scientist at the LIGO Hanford Observatory, described how he felt upon coming into the lab the morning of the detection, and his surprise upon learning that the signal was not a test. "Often we do tests on our detectors, called blind injections, where we simulate a gravitational-wave event," he said. "I raced into the lab and asked if we were in a blind injection phase—and to my everlasting amazement, I was told no."</p><p>"I don't know if you know the feeling," said panelist Alan Weinstein, professor of physics. "You spend 15 years working on something and then suddenly there it is staring at you in the face." (Adhikari noted that it took "easily a month" before he was convinced the detection was real.)</p><p>Weinstein, who described gravitational waves as the sound of the vibrations of spacetime itself, noted that LIGO had ended the "silence" of astronomy. "It's going to be a very loud future," agreed Whitcomb.</p></div></div></div>Thu, 03 Mar 2016 06:07:38 +0000schabner50012 at http://www.caltech.edu